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Updated: Jun 2, 2026
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Detection of Homologous Recombination Intermediates via Proximity Ligation and Quantitative PCR in Saccharomyces cerevisiae
Published on: September 11, 2022
Double rolling circle replication (DRCR) is recombinogenic
Haruko Okamoto1, Taka-aki Watanabe, Takashi Horiuchi
1Department of Basic Biology, School of Life Science, The Graduate University for Advanced Studies, Myodaiji, Okazaki, Japan.
Genes to Cells : Devoted to Molecular & Cellular Mechanisms
|April 20, 2011
Summary
Double rolling circle replication (DRCR) drives frequent DNA inversions and deletions/duplications. This mechanism may explain natural genome rearrangements and stimulate homologous recombination.
Area of Science:
- Molecular Biology
- Genetics
- Biochemistry
Background:
- Homologous recombination is crucial for genetic diversity and genome stability.
- Frequent DNA inversions occur in chloroplast DNA (cpDNA) and herpes simplex virus 1 (HSV-1) genomes, but the mechanisms are unknown.
- Previous work suggested frequent inversions in a double rolling circle replication (DRCR) system.
Purpose of the Study:
- To investigate the relationship between DRCR and hyper-recombination.
- To determine if DRCR is responsible for frequent DNA rearrangements.
- To propose a model for DRCR's role in homologous recombination.
Main Methods:
- Utilizing the yeast 2-μm plasmid and a designed amplification system.
- Inserting inverted repeats and direct repeats into the system.
- Observing and analyzing DNA inversion, deletion, and duplication events.
Main Results:
- DRCR was shown to be closely related to hyper-recombinational events.
- Inverted repeats induced frequent inversions in a DRCR-dependent manner.
- Direct repeats caused frequent deletions/duplications in a DRCR-dependent manner.
Conclusions:
- DRCR significantly stimulates homologous recombination.
- DRCR may be involved in natural chromosome rearrangements, cpDNA replication, and HSV genome replication.
- The study proposes a model where DRCR promotes homologous recombination.
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